The problem I see with this is scrambled rendering in IE6-SP1 & Firefox 1.0.4.
In particular, with Firefox the clickable area for some of the old article
revision overlap the radio buttons,
and with both browsers the radio buttons jump around as selected.

Like bug 2057, using the keyboard to tab through the active parts of the page
eventually allows selection.

Also, the tab sequence is out-of-order, with the "last" links sequenced
separately, but this is a separate issue also affecting LTR wikis, so I'll open
a new report for it.